matthews is at the university of denver, which is the site of tonight's debate. chris, i've been watching you this past hour. i can sense the excitement that you feel, that i feel as well. i mean, it is a big night when these candidates speak at their conventions, but tonight the tv audience for this debate could be almost twice the size as the convention audience. just a huge night. what are each of these guys thinking they need to do tonight? >> well, i think obama's the one i'm focused on, the president. because everybody's been talking about, it's romney's big chance, it's romney's opportunity, blah, blah, blah. suppose obama goes on the attack tonight. suppose he surprises everybody and doesn't play defense. he doesn't try to handle his opponent and clinch, that he really goes and tries to put him away. and i think that's the significanti i significanting question. how does romney deal with the fact that he has no spontaneity? no ability to deal with the unexpected? how does he deal with that in the debate for an hour and a half? so will obama go after the guy, not play defense, not